Re: [PATCH v2 net-next] net: phy: icplus: call phy_restore_page() when phy_select_page() fails

From: Michael Walle <michael@walle.cc>
To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Andrew Lunn <andrew@lunn.ch>,
	Heiner Kallweit <hkallweit1@gmail.com>,
	Russell King <linux@armlinux.org.uk>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	netdev@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH v2 net-next] net: phy: icplus: call phy_restore_page() when phy_select_page() fails
Date: Fri, 19 Feb 2021 11:46:23 +0100	[thread overview]
Message-ID: <b10a9b2cf171976e710c309fc82a4728@walle.cc> (raw)
In-Reply-To: <YC+OpFGsDPXPnXM5@mwanda>

Am 2021-02-19 11:10, schrieb Dan Carpenter:
> The comments to phy_select_page() say that "phy_restore_page() must
> always be called after this, irrespective of success or failure of this
> call."  If we don't call phy_restore_page() then we are still holding
> the phy_lock_mdio_bus() so it eventually leads to a dead lock.
> 
> Fixes: 32ab60e53920 ("net: phy: icplus: add MDI/MDIX support for 
> IP101A/G")
> Fixes: f9bc51e6cce2 ("net: phy: icplus: fix paged register access")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

Reviewed-by: Michael Walle <michael@walle.cc>

I assume, this has to go through "net" if the merge window is closed, 
no?

-michael

> ---
> v2: fix a couple other instances I missed in v1
> 
>  drivers/net/phy/icplus.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/phy/icplus.c b/drivers/net/phy/icplus.c
> index 3e431737c1ba..a00a667454a9 100644
> --- a/drivers/net/phy/icplus.c
> +++ b/drivers/net/phy/icplus.c
> @@ -239,7 +239,7 @@ static int ip101a_g_config_intr_pin(struct
> phy_device *phydev)
> 
>  	oldpage = phy_select_page(phydev, IP101G_DEFAULT_PAGE);
>  	if (oldpage < 0)
> -		return oldpage;
> +		goto out;
> 
>  	/* configure the RXER/INTR_32 pin of the 32-pin IP101GR if needed: */
>  	switch (priv->sel_intr32) {
> @@ -314,7 +314,7 @@ static int ip101a_g_read_status(struct phy_device 
> *phydev)
> 
>  	oldpage = phy_select_page(phydev, IP101G_DEFAULT_PAGE);
>  	if (oldpage < 0)
> -		return oldpage;
> +		goto out;
> 
>  	ret = __phy_read(phydev, IP10XX_SPEC_CTRL_STATUS);
>  	if (ret < 0)
> @@ -349,7 +349,8 @@ static int ip101a_g_read_status(struct phy_device 
> *phydev)
>  static int ip101a_g_config_mdix(struct phy_device *phydev)
>  {
>  	u16 ctrl = 0, ctrl2 = 0;
> -	int oldpage, ret;
> +	int oldpage;
> +	int ret = 0;
> 
>  	switch (phydev->mdix_ctrl) {
>  	case ETH_TP_MDI:
> @@ -367,7 +368,7 @@ static int ip101a_g_config_mdix(struct phy_device 
> *phydev)
> 
>  	oldpage = phy_select_page(phydev, IP101G_DEFAULT_PAGE);
>  	if (oldpage < 0)
> -		return oldpage;
> +		goto out;
> 
>  	ret = __phy_modify(phydev, IP10XX_SPEC_CTRL_STATUS,
>  			   IP101A_G_AUTO_MDIX_DIS, ctrl);

-- 
-michael